The committed version of /etc/rc.d/tmp depends on "mountcritremote" due to its use of grep.
This dependency can easily be removed to allow rc.d/tmp to be executed before /usr/bin is mounted.
Use of a here document avoids complications due to the spawned sub-shell if "df /tmp | while ..." was used.
In that case, the sub-shell would return a success code which then needed to be tested.
If a version without here-document was found to be preferential, I'd suggest a shell function that returns the result of "df /tmp | grep ..." but which does use the while loop from this patch instead of grep.